1. Field of Invention
The present invention relates to a power system used in an apparatus such as a camera that operates on batteries and also relates to a camera.
2. Description of the Related Art
There are power systems used in cameras in the related art that indicate the number of photographs that can be taken calculated based upon the remaining battery capacity and the power requirement for taking a single photograph. Such power systems include those disclosed in Japanese Laid Open Patent Publication No. H 10-341536 and Japanese Laid Open Patent Publication No. 2001-154250.
However, a camera power system in the related art such as those described above cannot calculate the exact remaining number of photographs that can be taken on the remaining power when it is adopted in, for instance, a digital camera, in which the battery power required per frame greatly varies depending upon the length of time over which the shutter release button is held halfway down, whether or not a strobe is used, the size of the image recorded, whether or not the image is displayed at the monitor and the like.
In addition, cameras come equipped with various functions today. Digital cameras, in particular, offer many functions. However, with a digital camera in the related art, a history of consumed battery capacity that has resulted in the presently remaining battery power level, i.e., which functions of the digital camera have been engaged to lead to the presently remaining battery power level, cannot be ascertained. If the history of the consumed battery capacity in the digital camera indicating specific functions that have been engaged can be ascertained, it will be possible to generate useful information based upon the consumed battery capacity history.